title: Biologic stability of plasma ion-implanted miniscrews.
abstract: OBJECTIVE
  To gain basic information regarding the biologic stability of plasma ion-implanted miniscrews and their potential clinical applications.
  
  
  METHODS
  Sixteen plasma ion-implanted and 16 sandblasted and acid-etched (SLA) miniscrews were bilaterally inserted in the mandibles of 4 beagles (2 miniscrews of each type per quadrant). Then, 250 - 300 gm of force from Ni-Ti coil springs was applied for 2 different periods: 12 weeks on one side and 3 weeks contralaterally. Thereafter, the animals were sacrificed and mandibular specimens including the miniscrews were collected. The insertion torque and mobility were compared between the groups. The bone-implant contact and bone volume ratio were calculated within 800 µm of the miniscrews and compared between the loading periods. The number of osteoblasts was also quantified. The measurements were expressed as percentages and analyzed by independent t-tests (p < 0.05).
  
  
  RESULTS
  No significant differences in any of the analyzed parameters were noted between the groups.
  
  
  CONCLUSIONS
  The preliminary findings indicate that plasma ion-implanted miniscrews have similar biologic characteristics to SLA miniscrews in terms of insertion torque, mobility, bone-implant contact rate, and bone volume rate.
authors.affiliation: Private Practice, Seoul, Korea.
authors.forename: Young-Chae
authors.initials: YC
authors.lastname: Cho
authors.forename: Jung-Yul
authors.initials: JY
authors.lastname: Cha
authors.forename: Chung-Ju
authors.initials: CJ
authors.lastname: Hwang
authors.forename: Young-Chel
authors.initials: YC
authors.lastname: Park
authors.forename: Han-Sung
authors.initials: HS
authors.lastname: Jung
authors.forename: Hyung-Seog
authors.initials: HS
authors.lastname: Yu
keywords: Histology; Orthodontic mini-implant; Stability; Surface treatment